{"cve":"CVE-2026-117601","nvd":{"published":"2026-10-27T14:16:39.947","modified":"2026-10-27T16:03:45.247","status":"Awaiting Analysis","description":"Electrum before 4.8.3 fails to verify signatures of wallet-owned inputs in unconfirmed mempool transactions, allowing malicious servers to replace a just-broadcast transaction with a conflicting one. Attackers can swallow the user's transaction and display an invalid zero-fee copy paying an attacker address, tricking users into RBF fee-bumping and signing it.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":9.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","score":7.5},"cwes":["CWE-347"],"references":["https://github.com/spesmilo/electrum/commit/90fe30822561e515a9d2d6e5a352cc07780999eb","https://github.com/spesmilo/electrum/security/advisories/GHSA-6jp4-8v48-cc5v","https://www.vulncheck.com/advisories/electrum-before-4.8.3-missing-signature-verification-of-mempool-transactions"],"products":[],"source":"nvd","synced_at":"2026-10-27T16:16:04.830248275+00:00"},"epss":null,"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}